BEHAVIOR OF BITUMINOUS ROAD MATERIALS UNDER ACCELERATED EXPOSURE CONDITIONS AND LABORATORY HEAT TESTS
ACCELERATED EVAPORATION TESTS, SUCH AS ASTM DISTILLATION TESTS, AS WELL AS THE TESTS FOR SO-CALLED ASPHALT CONTENT OR RESIDUE OF SPECIFIED PENETRATION, ASTM, AND THE TEST FOR LOSS ON HEATING ASTM ARE SUPPOSED TO SHOW IN A RELATIVELY SHORT TIME WHAT WILL TAKE PLACE WHEN THE VARIOUS MATERIALS ARE EXPOSED TO LIGHT, HEAT AND AIR, AND TO THE OTHER CONDITIONS MET IN THE HOT AND COLD PROCESSING OF BITUMINOUS SURFACES. THE ADEQUACY OF THESE TESTS TO PREDICT THE PROBABLE CURING AND HARDENING PROPERTIES AS WELL AS THE RELATIVE DURABILITY OF DIFFERENT MATERIALS BEFORE EMBRITTLEMENT DESTROYS THEIR USEFULNESS AS BINDERS IS OFTEN QUESTIONED. IT WAS THOUGHT THAT A COMPARISON OF THE CHARACTERISTICS OF THE RESIDUES DEVELOPED BY OUT-OF-DOORS EXPOSURE IN THIN-FILMS OR AS BINDERS IN MOLDED BITUMINOUS MIXTURES AND SURFACINGS WITH THE CHARACTERISTICS OF THE RESIDUE FROM ACCELERATED LABORATORY HEAT TESTS, INCLUDING THE 1/8 IN. THIN-FILM TEST FOR ASPHALT CEMENTS, MIGHT PROVIDE A BETTER UNDERSTANDING OF THE ALTERATIONS THEY UNDERGO WHEN EXPOSED UNDER ACCELERATED LABORATORY HEAT TESTS AND SIMULATED WEATHERING CONDITIONS. THE WORK ON LIQUID BITUMINOUS MATERIALS HAS SHOWN THAT THE PHYSICAL AND CHEMICAL CHARACTERISTICS GENERALLY ARE BELIEVED TO BELONG TO UNSATISFACTORY MATERIALS ARE DEVELOPED UPON EXPOSURE IN MANY PRODUCTS THAT SATISFACTORILY WITHSTAND LABORATORY HEAT TESTS. IT IS FURTHER BELIEVED THAT THESE ASPHALTS WHICH HAVE HIGH RESISTANCE TO ALTERATIONS WHEN PROTECTED EITHER BY LABORATORY MIXING TESTS OR EVEN MORE SEVERE TESTS, SUCH AS THE 1/8 IN. THIN-FILM OVEN TEST, WILL NOT HARDEN UNDULY IN NORMAL PLANT MIXING PRACTICE. SUCH TESTS SHOULD SERVE TO ELIMINATE THOSE ASPHALTS THAT HAVE LOW RESISTANCE TO THE HIGH-TEMPERATURE CONDITIONS OF PAVING PLANT AND CONSTRUCTION AND THEREBY RETARD THE EARLY CRACKING OF BITUMINOUS PAVEMENTS AFTER CONSTRUCTION.
-
Supplemental Notes:
- No 94, pp 14-39
-
Authors:
- Lewis, R H
- Publication Date: 1949
Media Info
Subject/Index Terms
- TRT Terms: Accelerated weathering; Asphalt cement; Bituminous materials; Bituminous mixtures; Bituminous pavements; Distillation; Durability; Evaporation; Heat; Oven tests; Pavement cracking; Sensitivity; Surface treating; Temperature; Test procedures; Testing; Thin films
- Uncontrolled Terms: Thin film oven test
- Old TRIS Terms: Bituminous surfacing; Retarding
- Subject Areas: Highways; Materials;
Filing Info
- Accession Number: 00210863
- Record Type: Publication
- Files: TRIS
- Created Date: May 13 1994 12:00AM